The present invention, in some embodiments thereof, relates to a closed-loop control system and, more particularly, but not exclusively, to a system and a method for stabilizing a single-track vehicle.
The single-track vehicle is a two-wheeled vehicle which generally creates a single track when moving straight ahead. The track of a front wheel and a rear wheel may follow different paths generally while turning or due to misalignment. Single-track vehicles may include, for example, a motorcycle, a scooter, a moped, a motorized bicycle and a bicycle.
Motorcycles are a fascinating mean of transportation, and have generally stimulated the imagination of men and women alike. In addition to offering a ride which is highly enjoyable, motorcycles occupy less space than cars and so contribute to a reduction in traffic load. In addition, motorcycles produce less pollution than cars.
Motorcycles are generally considered more dangerous than cars partly due to their relative instability. This instability is generally associated with a lateral displacement of a center of mass of the motorcycle from over the motorcycle wheels while stationary and/or in motion. Their instability also generally makes them less intuitive to operate, requiring that a motorcycle rider have a certain amount of motorcycle riding skill and training.
Numerous devices are known in the art which attempt to control the instability of a motorcycle.
US Patent Application Publication US 2008/0249684 A1 “OVERTURN PREVENTION CONTROL DEVICE FOR TWO-WHEEL VEHICLE”, relates to “An overturn prevention control device for a two-wheel vehicle having a vehicle body, a front wheel, an actuator that steers the front wheel, a rear wheel, and a rear-wheel driving portion, includes an angular velocity sensor and a control unit arranged to output a steering angle command signal for controlling the actuator. The angular velocity sensor includes a detection axis, is mounted on the vehicle body such that the detection axis is downwardly inclined at a predetermined angle relative to a forward direction of the vehicle body, and detects an angular velocity about the detection axis. The angular velocity detected by the angular velocity sensor includes an angular velocity in a lateral direction of inclination and an angular velocity in an azimuthal direction. The zero-set error and offset noise are incorporated into the azimuth angle command. Thus, the two-wheel vehicle can be prevented from overturning.”
US Patent Application Publication US 2007/0010919 A1 “TILT REGULATION DEVICE AND METHOD FOR REGULATING VEHICLE TILT” relates to “A tilt regulating device (16) for a vehicle (10), with detecting means (20) for detecting a roll velocity signal ({dot over (κ)}), representing the roll velocity of the vehicle (10), and for detecting a set steering angle signal (δLSET) with regulating means (21, 29, 30) for generating a steering signal (δL) on the basis of the roll velocity signal ({dot over (κ)}) and the set steering angle signal (δLset), and with output means (31) for outputting the steering signal (δL) to a steering actuator (15) for steering one or more wheels (11) of at least one axle of the vehicle (10). It is proposed that tilt regulating device (16) activates the steering actuator (15) by means of the steering signal (δL) in such a way that, at least for a certain time, the vehicle (10) is kept in a single-track driving mode.”
US Patent Application Publication US 2005/0197994 A1 “INTELLIGENT ROBUST CONTROL SYSTEM FOR MOTORCYCLE USING SOFT COMPUTING OPTIMIZER” relates to “A Soft Computing (SC) optimizer for designing a Knowledge Base (KB) to be used in a control system for controlling a motorcycle is described. In one embodiment, a simulation model of the motorcycle and rider control is used. In one embodiment, the simulation model includes a feedforward rider model. The SC optimizer includes a fuzzy inference engine based on a Fuzzy Neural Network (FNN). The SC Optimizer provides Fuzzy Inference System (FIS) structure selection, FIS structure optimization method selection, and teaching signal selection and generation. The user selects a fuzzy model, including one or more of: the number of input and/or output variables; the type of fuzzy inference; and the preliminary type of membership functions. A Genetic Algorithm (GA) is used to optimize linguistic variable parameters and the input-output training patterns. A GA is also used to optimize the rule base, using the fuzzy model, optimal linguistic variable parameters, and a teaching signal. The GA produces a near-optimal FNN. The near-optimal FNN can be improved using classical derivative-based optimization procedures. The FIS structure found by the GA is optimized with a fitness function based on a response of the actual plant model of the controlled plant. The SC optimizer produces a robust KB that is typically smaller that the KB produced by prior art methods.”
US Patent Application Publication US 2006/0085111 A1 “ROLL ANGLE CONTROL DEVICE FOR REMOTE-CONTROLLED TOW-WHEELED VEHICLE” relates to “A rolling angle control device 21 is disposed to provide the rolling angle control device for a remote-controlled two-wheeled vehicle so as to facilitate the control of the vehicle by an operator and stabilize the posture of the remote-controlled two-wheeled vehicle in a wide speed range.
The rolling angle control device 21 is provided with a rolling angle detection means 35 to detect a rolling angle of a vehicle main body, a steering actuator 13 to apply a right- or left-rotational torque to a steering shaft or a front fork, a control means 29 that outputs an operation amount for the steering actuator based on a rolling angle detection value and a rolling angle target value from a remote control receiver so as to bring the rolling angle detection value closer to the rolling angle target value, and a steering angle detection means 50 for detecting to which at least the neutral point as a boundary the steering angle is turned left or right, wherein a caster effect control means 51 is configured such that the control means 29 controls so that a signal is applied to an operation amount for the steering actuator as follows; when a steered angle detected by the steering angle detection means is in the right direction, the right-rotational torque is applied, and, when a steered angle detected by the steering angle detection.”
Additional background art includes EP1769990A “Slip control system for a single track vehicle and motor cycle with such a system”; JP2005271815A “AUTONOMOUS TRAVELLING TYPE MOTORCYCLE AND AUTONOMOUS CONTROL METHOD”; JP2006020652A “ROLL ANGLE CONTROLLING DEVICE FOR RADIO CONTROLLED MODEL, AND RADIO CONTROLLED MODEL BICYCLE”; KR200206602 A “UNMANNED MOTOR BICYCLE BY USING GYRO”; and JP7215258A “MOTORCYCLE”.